If your Learning Management System (LMS) users receive the message API Login Failed Oauth_signature incorrect credentials and/or signature calculation this can be due to two different reasons, depending on the user type. Please refer to the relevant tab below:
If a student encounters this error message when attempting to access Turnitin LTI assignments, this may be related to the names that have been entered in the student's user profile in the LMS.
To try to resolve this error, the LMS administrator should review the user's details, completely remove the existing data, and then re-enter it (without using the cut-and-paste method to enter text).
If instructors encounter this error message when trying to access a Turnitin LTI assignment, the Turnitin LTI external app may have been configured multiple times within the Administrator External apps.
This error may also occur if the app is already configured at the account level and an instructor configures the app for an individual course as well.
The Turnitin LTI external app only needs to be configured once at the account level, so any duplicates or configurations at the course level will need to be removed.